Autocollimating reflector



y 2, 1933- A. GARBARINI 1,906373 AUTOCOLLIMATING REFLECTOR Filed July 7, 1930 Fig.2

Patented May 2, 1933 GARIBARINI, OF COURBEVOIE, FRANCE, ASSIGNOR, BY MESNE ASSIGNMENTS,

TO LIBBEY CATAPHO'I'E CORPORATION, OF TOLEDO,

OHIO

OHIO, A CORPORATION OF AUTOCOLLIMATIN G REFLECTOR Application filed July 7, 1930, Serial No. 468,233, and in France October 17, 1929.

Autocollimating devices having a con possible to assemble a large number of units m a given space determined by the dimension of the signal to be displayed. As the most favourable ratio between the diameters of the collimating lens and of the object lens is 2 to 1, it follows that in every direction the distance between axes is at least equal to D, D

being the diameter of the large collimating lens.

Now, as far as, for example, signals for motor cars are concerned, since these vehicles only move in a horizontal plane, only the horizontal field is of interest.

' The present invention which is based on this consideration, consists in eliminating the vertical field by cutting the collimating lens along two parallel planes the distance be- 2 tween which is variable and practically equal to the diameter of the small object lens, whereby the density of the units forming the signal, and consequently, the luminosity, may be doubled without in any way modifying the useful characteristics of these units.

Figs. 1, 2 and 3 of the accompanying drawing illustrate by way of example in front elevation, end elevation and plan respectively, an embodiment of an autocollimating unit in accordance with the invention,

Fig. 4 is a front elevation of an embodiment of a signal made up of units of the type illustrated in Figs. 1 and 2.

Fig. 5 is an elevation of the signal in section along the line IV-IV Fig. 4.

Fig. 6 is a sectional VIVI Fig. 4.

Fig. 7 is a plan view of a signal in the form of a portion of a cylinder and having an angular range greater than 180.

plan View along Fig. 8 illustrates a hemispherical signal in front elevation.

Fig. 9 is an elevation in section along the line VIII-VIII, Fig. 8.

As may be seen in this drawing, (Figs. 13) an autocollimating unit according to the invention comprises a small hemispherical object lens 1, contacting along a diametral plane with a collimating lens 2 in the form of a hemisphere truncated by the parallel planes P P. which may for example be practically tangent to the hemisphere 1. The radius of the lens 2 will be preferably double that of the lens 1.

The back 2 of said lens 2 is faced in 2' known manner with a coating of silver and a coating of varnish.

To form a signal 3 for motor vehicles (Figs. 4 to 6), the units are placed in vertical rows in such manner that the cutting planes of the lenses 2 run horizontally, the block being cast. The useless vertical field is thus eliminated. As illustrated in Figs. 4 to 6, the units are preferably placed in staggered relation. The bulk is thus reduced and the reflecting surface between the object lenses 1 is utilized to the best advantage.

The units in accordance with the invention adapt themselves to the formation ofa signal 4 (Fig. 7) having a covering range greater than 180 and in which the surface of the system instead of being planar is a portion of a cylinder. The units may likewise be grouped to form ronos signals 5 (Figs. 8 and 9) in which the surface from which the object lenses project is a spherical cap.

. It will be readily understood that for other applications it might be useful to eliminate the horizontal field in which case the signal would be simply turned through 90.

I claim: a

1. A signal formed by a plurality of auto collimating sights each comprising in com bination a hemispherical objective lens, a larger hemispherical reflector joined to said planes between which said objective lies, the.

ratio of the radii of said lenses being a function of the refractive index of the .glass ofwhich said lenses are made, while the distance between the centers of said lenses, which are coaxial, is proportional to the desired divergence of the reflected light, the reflector lens of each unit being in contiguity with adjacent reflectors along the aforementioned cutting planes.

2. A signal formed by a plurality of autocollimating sights formed in a single casting and each comprising in combination, a hemispherical objective lens, a larger hemispherical reflector joinedto said objective and truncated by two parallelplanes between which said objective lies, the ratio of the radii of said lenses being a function of the refractive index of the glass of which said lenses are made, while the distance between the centers of said lenses, which are coaxial, is

proportional to the desired divergence of the reflected light, the reflector lens of each unit being in contiguity with adjacent reflectors along the aforementioned parallel cutting planes. I

3. A signal formed by a plurality of autocollimating sights formed in a single casting and each comprising, in combination, a hemispherical objective lens, a larger hemispherical reflector joined to said objective and truncated by two parallel planes between which said objective lies, the ratio of the radii of said lenses being a function of the refractive index of the glass of which.

said lenses are made, while the distance between the centers of said lenses, which are coaxial, is proportional to the desired divergence of the reflected light, and a coating of shining metal on the outer face of said reflector remote from said objective, the reflector lens of each unit being in contiguity with adjacent reflectors along the aforementioned parallel cutting planes.

4. A signal composed of a plurality of autocollimating sights formed in staggered relation ina .single casting and each comprising, in combination, a hemispherical objective lens, a larger hemispherical reflector joined to said objective and truncated by two parallel planes between which said objective lies, the ratio of the radii of said.

lenses being a function of the refractive index of.the glass ofwhich said lenses are made, while the distance between the centers of said lenses, which are coaxial, is proportional to the desired divergence of the' reflected light, the reflector lens of each unit being in contiguity with adjacent reflectors. along the aforementioned parallel cutting" signal formed a plurality of autospherical objective lens, a larger hemispherical reflector joined to said objective and trun cated by two parallel planes tangential to said objective at the ends of a diameter thereof, the ratio of the radii of said lenses" being a function of the refractive index of the glass of which said lenses are made, while the distance between the centers of said lenses, which are coaxial, is proportional to the desired divergence of the reflected light, the reflector lens of each unit being in contiguity with adjacent reflectors along the aforementioned parallel cutting planes.

6. A signal formed by a plurality of autocollimating sights each comprising, in combination, a hemispherical objective lens, a larger hemispherical reflector joined to said objective and truncated by two parallel planes between which said objective lies, the reflector lens of each unit being in contiguity with adjacent reflectors along the aforementioned parallel cutting planes.

7. A signal formed by a plurality of autocollimating sights formed in a single casting and each comprising, in combination, a hemispherical objective lens, a larger hemispherical reflector joined to said objective and truncated b two parallel planes between which said ob ective lenslies, and acoating of shining metal on the outer face of said reflector remote from said objective, the reflector lens of each unit being in contiguity with adjacent reflectors along the aforementioned parallel cutting planes. v

. 8. A signal composed of a plurality of autocollimating sights formed in staggered relation in a single casting and each comprising, in combination, a hemispherical objec-' tive lens, a larger hemispherical reflector joined to said objective and truncated by two parallel planes between which said objective lies, the reflector lens of each unit being in contiguity with adjacent reflectors along the aforementioned parallel cutting planes.

9. A signal formed by a plurality of autocollimating sights formed in a single casting and each comprising, in combination, a hemispherical objective lens, a larger hemispherical reflector joined to said objective and truncated by two parallel planes tangential to said objective at the ends of a diameter thereof, the reflector lens of each unit being in contiguity with adjacent reflectors along the aforementioned parallel cutting planes.

10. A signal formed by a plurality of autocollimating sights each comprising in combination a hemispherical objective lens, a larger hemispherical reflector joined to said objective and truncated ;by two parallel planes between which said objective lies, the reflector lens of each unit being in contiguity with adjacent reflectors along the aforementioned cutting planes.

11. A signal formed by a plurality of autocollimating sights each comprising a convex objective lens through which incident and reflected light is transmitted, a cnncave reflector in axial alignment therewith and truncated by two parallel planes between which the objective lies, the diameter of the reflector 0n aline parallel with said lanes being greater than the diameter of e objective lens, and the objective lenses being arranged in spaced rows extended transversely of said planes.

*- GARBARINIQ 

